Perforating machine for well casings



July 7,'1931.

2 Sheets-Sheet l A9 ILIZII Attorney July 7, 1931. A. E. CARTER E'r-Al. K 1,313,144

PERFORTING MACHINE FOR WELL GASINGS Filed Aug. 3l, 1929 2 Sheets-Sheet 2 i ,Bymmn i Attorney Inventor Patented July 7, 1931 UNITED STATES" APMENr ARTHUR E. OARTER ANDv CLARENCE A; JOHNSON, OF sAN 'BEaNARnINd CALIFORNIA c PnRFOaATiNe MACHINE non WELL OAsINGs Application` filed August 31, `1929. ySerial No.Y 389,840.

' This invention relates broadly' to perforating machines andhasmore particular reference to a perforating machine `especiall'y adapted for perforating the walls of well casings, the primary object ofthe. invention being tofprovide a device of this nature, which is capable of disposition in the well casing, Vand `including a plurality vof pivotally mounted knives normally maintained in an inoperative positionbut which,

upon the applicationfof force to the device, .will be moved to a cutting position for piercing` the walls yof the casing. A still further object of the invention is to provide a device yof this'nature, adapted to be suspended in the well casing through the me-.

dium ofthe usual well equipment for this purpose and which may be worked up vand down in the casing so that the knives of '20 the device may penetrate the vwalls of the well casing for perforating the same.

A stillfurther object of the invention is to provide a device of this nature, which is simple inconstruction, strong, durable, thoroughly reliable, practical and eiicient in koperation and otherwise well adapted to the purpose. designed. v Otherobjects and advantages of the invention will become apparent during a study of the following description, taken in connection with the accompanying vdrawings,wherein: j f

Figure 1 isa side Velevation vof a well casing perforating machine constructed in accordance with the present invention, and showing the knives inan inoperative position, and the device prior toits insertion in thewell. .f f

Figurer2 .is a top plan viewf thereof with the concaved knife. backing plate being shown in transversesection.

l Figuref ,isa front, elevation of a knife backing plate. i ,Y y, Figure 4 is a perspective view of one of the perforating knives.

`Figure 5'is an end elevation of one of the perforating knives. Y K

Figure 6 is a ldetail view, partly in sec.- tion and partly in elevation of the device when the knives are in' a cutting position.

Figure 7 is atrans'verse 'detailsectional view, taken substantially on the line 7 7 of Figure 6. -1

Figure 8 is a fragmentary detail longitul dinal sectionalviewof the lower end of fthe main handle.' f f Figure 9 is atop plan viewwof the spider showing `the same in position" on thef man# drel, the mandrel being shown in section. i

WithV reference more vfin detailiito the drawings, .it will be seen that `my improved perforating machine for well lc'a'sirigs com-fv prises an elongated rod'orfmandrel 5,- which rod or mandrel 45 'is preferably "squarefin cross section and at its upper endv terminates in 'the reduced taperedl externally threaded end 6, adapted to be threadedly received in a suitable device, whereby the machine may be suspended from a set of jars, which jars form a part of the .wellequipment and in the art are well known as being standard equipment for such work. At spaced lon'gi; tudinal points and inwardly from the ends', the mandrel is providedl with the upper stop 'collar 7 and a lower stop collar 8. `An upper spider 9 comprises a rectangular hub 10,v through which the upper end ofthe `man-z drel 5' extends for slidably supporting said spider on the'end ofthe mandrel, the spiderl having the arms 11 extending one from Aeach of the four sides -of the hub as shown to advantage in Figure9. IIn normal position,

the'hub 10 of the spider 9 will rest upon the collar 7. A lower spider, designated generally by the reference character 12 has a rectangular hub- 13, from the sides of which extend the arms 14, the spider 12 being vsubstantially the same in construction as the spider 9, withthe exception that the hub 13 extends beyond the lower edges ofthe armsV 14 as shown to advantage in Figure "6. l The upperv and lower spiders-1 are connected through the medium of vertical arms or links designated generally by the reference Ycharacter'l. Thereare a plurality fof these rarms 15 and each of the arms are identical in construction, each arm being formed at its o posite ends with lateral inturned termina sV 16716, and the terminals 16 "are provided l with -a` pluralit7 of longitudinally 'lisv aligned spaced perforations or openings 17. In practice, a pair of the arms 15 connects an arm 11 of the upper spider with a corresponding arm of the lower spider, and the apertures 17 on the lateral ends 16 of the links or arms 15 are adapted-to be selectively registered with an opening 18 formed in the respective arms of the upper and lower spiders, a bolt 19 being passed through the re istering apertures 17 and 18 for securing th a`insin`ah adjiistedposition'onthe arms of the spider. The length of the arm is greater than the distance between the eollars 7 and 8, so that normally when the upper spider is at rest onv its collar 7 the lower spider will be positioned downwardly and out ofcontact of the-lower collar 8 or the respective positions of the spider will be such as shown to advantage in Figure 1. Cutting and perforating knives 2O have one end thereof pivoted between a pair of ears 21, which pairs of ears 21 project laterally from,I each sideof the mandrel 5, the pivot pin for the'knives being designated as at 22. The outer free ends of the knives 20 are adaptedfor vertical pivotal movement between the respective pairs of vertical arms or linksv 1'5, the outer free end of the knives projecting beyond the arms 15, for movement in the' longitudinal slot 23, rformed in the respective elongated knife backing plates 2,4, which plates 24 are of concaved formation' in crss section as shown to advantage in Figure 2, and these plates 24 are secured atA their upper and lower ends to the arms y1.1 and 14,- respectively, of the upper and lower s iders,the upper and lower vertical edges o the `plates being bent inwardly as at 25-against the outer lower and upper edges of ,the links 15M of the respective pairs of links. The plates 24' have their vertical side edges extending laterally from the adjacent si'de ofthe ,links 15 of the respective pairs asis also shown to advantage in Figure 2. Trip arms 26 are pivoted at their upper ends to the arms 11 -of the topmost spider 9',v adjacent the hub of the spider, and said trip arms 26 at`their lower ends are offset as at27, the terminals of the offset ends of the arms being pivoted to the respective knives 20. I

Normally the arms are in that position shown in Figure 1 or in a non-cutting position and lin order to move the arms in a horizontal or cutting position as shown in Figure 6, there 4is provided a coil spring 27 dis osed about the lower end of the mandrel 5t 1e lower end of the coil' spring impinging against a collar 28 threaded on the extreme lower endjy of the mandrel, Vand a pin 29 extending through the collar and the mandrel to prevent casual rotation of the collar. The spring 27. is normally in a compressed posi'- tion and for maintaining the l in in this comor of some low shearing strength material is inserted in a suitable opening provided therefor in the side of the mandrel 5, a considerable distance beneath the lower end of the collar 8 so as to be below the lower edge of the hub 13 of the lower spider 12 when said spider 12 is at its lowest position as shown to advantage iny Figure l. The operation of our device may be briefly described as follows: The device is normally in the position shown in Figure 1, that is, with the hub of the uppermost spider 9 resting upon the upper collar' 7, so that the hub of the lower spider is disposed a suitable distance below the lower collar 8, the spider being in this position.A The cutting knives 2O are disposed in the inclined position shown in Figure 1,;while the spring 27 is compressed between the collar 28 and the pinor peg 30. At their cutting ends the knives 20 adjacent their upper edges are serrated to provide penetrating or piercing teeth 31, while the lower edge of the knives, at the free ends thereof are suitably Vsharpened to provide cutting edges as at 32. j

Obviously then, the mandrel having its pin 6 threaded in a suitable jarring apparatus, the device with its parts arranged in the position' just described, is4 loweredy into the well casing, and the device is lowered into the casing with sufficient force as to forcibly engage' the lower end of the mandrel with the bottom of the well one or more times, and the lower' end of the mandrel thus repeatedly forced against the botA tom of the well will set' up sufficient vibration upony spring 27, the same being noremally retained in a' partially contracted position'between'collar 28 and the relatively fragile pin 30.- Sucli action will manifestly cause alternate contraction an'd expansion of the spring with the result that therpin A3() will gradually become weakened andfinally shear-ed thus freeing the spring so that the same upon expansiony willY abut hubA 1-3, and, at its upper end,'the spring thus contacting with sufficient force against the lower end of the hub 13 of the lower spider 12, thus forcing the spider 12 and upper spider 9 upwardly longitudinally of the mandrel, so that the hub 13' will abut the lower collar 8, and this action'l of the spider will of course draw the trip rod 26 upwardly, thus movingl the critter knives" 20 to a substan tially horizontal or cutting position with the working edge of the' knives extending through the slotsV of' the plates,` 24, 'the knives being draw-n up with s'uii'cient force as to have their serrated teeth puncture the well casing. Obviously,y successive blows from above or a series of jerks will cause an up and down 'sliding movement of the respective spiders, thus continuously mev- .166 pressed positiona pin 3() pre erably of wood ying the knives about their pivots for pro llU Manifestly, when the device is raised out of the well casing, the lknives will return to the originalposition shown inr Figure landy the operation may bey repeated at any desired height within the well casing. It will be necessary to replace pegs on the mandrel only at the beginning of the operation of the device as will be apparent; v

The knives are preferably of tool steel temper andthe teeth and cutting edge of the knife will permit cutting operation of the knives with a minimum amount of eX- pended energy.

lt is believed that from the foregoing description taken in connection with the ac-y companying drawings, a clear understanding of the operation, construction and advantages of the well casing perforating tool or machine of this ycharacter will be had by those sufficiently skilled in this art. A more detailed description thereof is deemed unnecessary.

Even though we have herein shown and described the preferred embodiment of our invention, it is to be understood that the same is susceptible to changes fully coinprehended by the spirit of the invention as herein described and the scope .of the appended claims.

Vihat is claimed is:

l. In a device ofthe class described, a mandrel adapted for disposition iii a well casing, a spider slidably supported on the mandrel adjacent one end of the mandrel, a second spider slidably supported on the mandrel adjacent the opposite endof the mandrel, means operatively connected to the spiders for maintaining said .spiders in a .predeterminedspaced relation on said maiidrel, cutting knives pivoted to the mandrel at the sides of the mandrel intermediate said spiders, trip bars pivoted to the knives and to one of said spiders, a compressible spring convoluted about said mandrel adjacent the lower end thereof, a shearable pin extending transversely through the mandrel and engaging said spring for' normally retaining the latter in a compressed condition, and said spi'ing adapted upon expansion thereof to bear against said second spider for urging said spider upwardly longitudinally of the mandrel, whereby said cutting knives are swung vertically about their pivots to a substantially horizontal positiony for cutting engagement with the wall of a well casing.

2. In a perforating device for well casings, a. mandrel adapted for suspension in the well casing, a spider slidably supported on the mandrel adjacent one end of the mandrel, a second spider slidably supported on the mandrel adjacent the other end of said mandrel, vertically disposed arms secured at their ends to the respective spiders for maintaining saidjspider's .in'spaced relation' on saidinandrels, a pluralityfof cutting knives, means pivotally connecting said ycutting knives to the sides of the mandrel interme-vv diate saidfspiderstrip `arms pivoted to said knives and to lone of said spiders, said trip f movement of said' spiders for moving said arms to a horizontal position for engagement with'the well casing, and actuating means engaging the mandrel and one of the spiders for imparting sliding movement to said spiders". f g

3.: In a perforating devicefor well casings, a mandrel adapted for suspension in the well casing, a spider slidably-,supported on ythe mandrel adjacent one .end of the mandrel, a: second spidery slidably supported on the mandrel adjacent the other end of said mandrel, vertically disposed arms secured at their ends to the respective spiders for main taining said spiders lin spaced*v relation Von said mandrels, a plurality'of cuttingknives, means pivotally connecting said cutting knives to the sides of the mandrel interine-A diate said spiders, trip arms pivoted to said,

lai-ms adapted to be actuated uponslidingv means for the spiders adjacent Vone of the i spiders for yimparting sliding movement t0 4saidspiders, said-last mentioned means lcomprising an 'eXpansible spring convoluted about the lower end of said mandrel, said spring having one end thereof fixed to said mandrel, and a shearable peg extending transversely through said mandrel and projecting laterally from opposite sides of the mandrel for engagement with the free end ofthe spring for normally'retaining vthe same ina compressed condition.r f Y 4. In a perforatiiig device for well casings, a mandrel adapted for suspension in .'thewell .casing, a spider slidably supported on the vmandrel adjacent one end Of'vvthe mandrel, a second spider slidably supported len the mandrel adjacent the 'other end of said mandrel, vertically disposed arms secured at their ends to" the respective spiders for'maintaining said spiders infspaced reladie tion on said mandrels, av plurality offcutting knives, means pivotally connecting, said cutting knives to the sides of the mandrel kintermediatesaid spiders, trip arms pivoted to said knives and to one of said spiders, said trip arms adapted to be actuated' upon 4sliding movement of saidspiders Yfor moving said arms to a horizontal position for env Ygagement with the Well casing, and actuat ing means for the spiders adjacent one of the spiders for imparting sliding movement` toy said'vspiders, said last mentioned means comprising a normally compressed expansible spring convoluted about said mandrel, said spring having one end thereof fixed to said mandrel and the other end of said spring adapted to bear against said adjacent one of said spiders upon expansion of said spring, and a member carried by said mandrel bearing against the free end of said spring for normally retaining the latter in a compressed condition, said member adapted to be sheared under the expansible action of said spring when said one end of the mandrel is forcibly struck against the bottom of the Well, said knives at their free ends being provided with a cutting edge.

5; In a perforating device for well casings, a mandrel adapted for suspension in thevvell casing, a spider slidably supported on the mandrel adjacent one end of the mandrel, a second spider slidably supported on the mandrel adjacent the other end of said mandrel, vertically disposed arms secured at their ends to the respective spiders for maintaining said spiders in spaced relation on said mandrel, a plurality of cutting knives, means pivotally connecting said cutting knives to the sides of the mandrel intermediate said spiders, trip arms pivoted` to said knives and to one of said spiders, said trip arms adapted to'be actuated upon sliding movement of said spiders for moving said' arms to a cutting position in engagement with the well casing, a` collar on one end of said mandrel, a shearable pin extending transversely through the mandrel remote from said collar, a normally partially compressed coiled spring convoluted about said mandrel between said collar and said pin and having one end normally enaging said pin whereby upon the repeated jerkingof said mandrel, or repeated forcible engagement of one end of said mandrel with the bottom of the well, said spring will be effective for forcibly shearing said pin whereby upon expansion of the spring subsequent to the shearing of said pin said spring will engage an adjacent one of said spiders for urging both of said spiders relative to said mandrel, and said knives at their free ends being provided with cutting edges, and teeth on the free ends of said knives above said cutting edges.

6. A device for perforating well casings comprising in combination a mandrel, a spider slidable thereon, a collar iXed to said mandrel adjacent one end thereof, a shearable pin extending transversely through the mandrel in spaced relation to said collar, a coiled spring convoluted about said mandr'el and normally retained in a partially contracted position between said collar and said pin, a plurality vof cutting knives pivotedl at one end to the mandrel, means operatively connecting said cutting knives with said spider for effecting swinging movement of the knivesupon movement of ARTHUR E. CARTER. CLARENCE A. JOHNSON.

tures. 

